Laminated paper board carton



June 26, 1962 J. F. KlLLlON 3,040,959

LAMINATED PAPER BOARD CARTON Filed Nov. 21, 1958 5 Sheets-Sheet 1 INVENTOR! JOHN F. KILLION ATTORNEY June 26, 1962 J. F. KILLION 3,040,959

LAMINATED PAPER BOARD CARTON Filed Nov. 21, 1958 3 Sheets-Sheet 2 T'IE EI INVENTOR JOHN F. KILLION ATTORNEY June 26, 1962 J. F. KILLION 3,040,959

LAMINATED PAPER BOARD CARTON Filed Nov. 21, 1958 3 Sheets-Sheet I5 INVENTOR JOHN F. KILLION By A ex. AfiWPW WZJ- ATTO R N E'Y rates Fatent ice 3,040,959 LAMKNATED PAPER BOARD CARTON John F. Killian, Philadelphia, Pa., assignor to FMC Corporation, a corporation of Delaware Filed Nov. 21, 1958, Ser. No. 775,463 4 Claims. (Cl. 229-37) This invention pertains to the art of packaging and more particularly relates to an improved paperboard carton of laminated construction, and to a method of sealing the carton that facilitates opening the same.

Reference is made herein to my copending application entitled, Moistureproof and Siftproof Carton, Serial No. 736,565, filed May 20, 1958, now abandoned, wherein a specific hermetically scalable carton structure is disclosed.

An object of the present invention is to provide a carton of the type disclosed in said copending application which is easily opened by the consumer.

Another object of the invention is to provide a carton material of laminated construction which may be delaminated to facilitate opening a carton made from said material.

Another object of the invention is to provide a method of closing a carton wherein heat is applied to selected areas of the carton flaps to delaminate the carton stock in those areas in a manner that facilitates opening the carton.

These and other objects and advantages of the invention will become apparent from the following description and the accompanying drawings, in which:

FIG. 1 is a fragmentary illustration showing one end of a carton blank adapted to be used in the formation of the carton of the present invention.

FIG. 2 is a fragmentary perspective illustrating the laminated construction of a piece of the carton stock from which the blank of FIG. 1 is fabricated.

FIG. 3 is a fragmentary perspective of a carton formed from the blank of FIG. 1, with the upper end flaps opened to a position projecting outward from the body of the carton, and illustrating the pattern of application of a bonding agent to parts of the end flaps for the purpose of sealing the carton.

FIGS. 4, 5 and 6 are perspectives showing successive steps in the closing and sealing of the carton, contemplated by the present invention.

FIGS. 7 and 8 illustrate the manner in which the carton of the present invention can be opened by the consumer.

FIG. 9 is a fragmentary perspective illustrating the manner in which a partially emptied carton can be reclosed.

FIGS. 10, 11 and 12 illustrate the manner in which a carton closed by a modification of the method of the present invention can be opened by the consumer.

Referring now to the drawings and particularly FIG. 1 thereof, the carton blank partly illustrated therein comprises a front panel 12, a rear panel 14, two side panels 16 and 18 and a short tab 20 adapted to be fastened to the inner surface of the side panel 18 to form an openend tube of rectangular cross section. A rectangular end flap 22 is connected to the panel 12 and, similarly, end flaps 24, 26 and 28 are connected to the side panels 14, 16 and 18, respectively. A small end flap 29 is connected to the tab 28. Score lines 30, 32, 34 and 36 separate the tab 20 and the panels 12, 14, 16 and 18, and are the folding lines on which the blank is folded in order to form the rectangular body portion of the carton of the present invention. Similarly, a score line 37 is formed between the tab 20 and the flap 29, a score line 38 is formed between the panel 12 and the end flap 22, a score line 40 divides the end flap 26 from the panel 16, a score line 42 divides the end flap 24 from the panel 14 and a score line 44 divides the end flap 28 from the panel 18. A diecut 50 separating the end flap 26 from the end flap 24 terminates a predetermined distance short of the score lines 40 and 42 for the purposes described in said copending application. A similar diecut 52 separating the end flap 24 from the end flap 28 terminates a predetermined distance short of the score lines 42 and 44.

The end flap 22 is provided with three extensions in the form of tab portions 60, 62 and 64, respectively, which extend outwardly from the three unconnected edges of the flap 22 for reasons which are explained in the abovementioned copending application. A diecut line of perforations 66 is provided on end flap 24 parallel to the score line 42 and spaced therefrom a distance substantially equal to the width of the tab extension 62 on the end flap 22 to define a tear line along which the flap 24 may be torn so as to leave a narrow strip 67 thereof still connected to the side panel 14 along the hinge line 42.

The laminated carton material of the present invention is best understood by reference to FIG. 2 of the drawings and comprises the usual paperboard carton material 68, a layer of low melting point bonding agent 70 and a layer of carton lining material 72 bonded to the paperboard material 68 by the bonding agent 70. The particular lining material used depends on the material to be packaged in the carton, and would be chosen according to the particular protection characteristics required, from a number of materials among which would be included foil, glassine, plastics, Pliofilrn, polyethylene and saran.

Similarly, the bonding agent 70 can be chosen from a number of bonding agents, including various waxes and paraflins, having a lower melting point than the material chosen for the liner, and capable of creating a bond that can be destroyed by the application of heat. By way of example, if a Wax is used as the bonding agent between the laminae of the laminated material and heat is applied to the outer surface of the paperboard lamina, the wax bonding agent will melt and be absorbed by the paperboard material. Thus, the bond between the paperboard material and the inner lamina of coating material will be destroyed in those areas where heat has been applied.

After the bottom (not shown) of the carton has been closed and sealed in any conventional manner the material to be packaged is introduced into the carton through the open upper end thereof and a bonding agent is applied to the areas indicated at 74, 76 and 78 in FIG. 3 of the drawings, these areas being narrow strips extending across the end flaps 26, 24 and 28, respectively, adjacent and parallel to their hinge lines 40, 42 and 48, respectively. The bonding agent so applied should be of the type which is either thermosetting or at least thermostable to the extent that it isunaffected by the heat required to desroy the bond between the laminae of the carton material.

The fiap 22 is then folded to the position illustrated in FIG. 4, and heat is applied to the upper surfaces of the tab extensions 60, 62 and 64. This sets the bonding agent on the areas 74, 76 and 78 so that the inner lamina 72 on the surfaces of the tab extensions 69, 62 and 64 is bonded to the inner surfaces of the flaps 24, 26 and 28. This application of heat likewise destroys the laminating bond between the inner lamina 72 and the outer lamina 68 and thus delarninates the carton material in the areas of said tab extensions 60, 62 and 64. A bonding agent 89 is now applied to a narrow area adjacent the free end of the flap 24 on the inner surface thereof, as illustrated in FIG. 5. The end flaps 26 and 28 are folded inwardly as illustrated in FIG. 5, and the end flap 24 is folded over and bonded to the upper surface of the end flap 22 as illustrated in FIG. 6.

When the consumer desires to open a carton sealed in this manner, he grasps either end portion of the flap 24 and pulls upwardly. The flap 244 will tear along the perforation line 66 and will pull loose from the upper surface of the flap 22 since the bonding agent 80 has been applied to a limited area. After all of the flap 24- except the narrow, hinged strip 67 thereof has been removed in the manner just described, the remaining flap portion 67 and the end fiaps 26 and 28 are unfolded from their overlapping relation with the end fiap 22, and outwardly to their positions illustrated in FIG. 8. In this condition, the carton is still sealed since the end flap 22 remains in its closed position, and the inner lamina or liner 72 on the surfaces of the tabs 60, 62 and 64 is sealed to the inner surfaces of the flaps 26 and 28 and the portion of the end flap 24 which still remains; i.e., the narrow strip 67.

The consumer now grasps the paperboard lamina of the tab extension 62 or 64, which was delaminated from the inner lamina or lining material 72 when the carton was sealed, and pulls upwardly in the manner illustrated in FIG. 8 thus tearing the inner lamina 72 substantially along the crease lines defining the hinged edges of the tab extensions 69, s2 and 64, because the marginal regions of the inner lamina 72 that overlie these tab extensions are bonded thereto, whereas the portion of the lamina 72 that underlies the end flap 22 has not been delaminated therefrom and therefore remains bonded thereto.

If only a portion of the material packaged in the carton is to be used and it is anticipated that it will be desired to reclose the carton, the end flap 22 should not be removed completely, but should be permitted to remain joined to the side panel 12 along the score line 38, which thus becomes a hinge line about which the flap 22 can be turned, thus opening the associated end of the carton and and making the cartons contents easily accessible and easily removable. Then, when it is desired to re-close the carton, the tab extensions 60, 62 and 64 should be folded downwardly to positions substantially at right angles to the plane of the flap 22 and then slipped inside of the carton as the flap 22 is turned inward to carton closing position. It will be appreciated that the carton reclosed in this manner will no longer be vaporproof or siftproof; however, it will remain greaseproof, if such were the characteristic of the lining material originally chosen.

FIGS. 10, 11 and 12 illustrate the opening of a carton which has been closed by a modified form of the method previously described. In this modified form of the method of closing the carton, the only difference from the procedure discussed above is that when the carton is being sealed, the application of heat is made not only to the tab extensions 60, 62 and 64, but to the entire upper surface of the end flap 22. Thus, after the major part of the outermost end flap 24 has been removed, as indicated in FIG. 10, and the strip 67 and tab extensions 26 and 28 have been turned outward, the paperboard part of the entire end flap 22, including the tab extensions 60, 62 and 64 connected thereto, may be opened outwardly as illus trated in FIG. 11, while the carton remains sealed by the inner lamina 72 which was delaminated from the inner surface of the end fiap 22 and the tab extensions 60, 62 and 64 during the sealing operation. When it is desired to empty the contents from the package sealed in this manner, the rectangle of the inner lamina 7 2 which extends across the opening of the package is removed, as illustrated in FIG. 12. It should be evident that the package sealed in accordance with the alternate method may be reclosed in the same manner as discussed above and illustrated in FIG. 9.

While two embodiments of the present invention have been disclosed herein, it should be understood that various modifications and changes may be made therein without departing from the spirit or scope of the invention as defined in the appended claims.

Having thus described my invention what I claim and desire to secure by Letters Patent is:

1. A carton made of laminated material having inner and outer laminae bonded together, said carton having a plurality of panels connected together to form a tubular structure, said panels having hinge lines at corresponding edges at one end of said structure, said hinge lines being aligned in juxtaposition to define a plurality of end flaps adapted to be successively folded inwardly to superposed relation to close the carton, the end fiap which is first folded inwardly having a central portion substantially coextensive With the space defined by said hinge lines and having outwardly projecting tabs, the inner lamina of said tabs being sealed to the inner lamina of others of said end flaps to seal said carton, the inner lamina of the carton material being delaminated from the outer lamina completely in said outwardly projecting tabs whereby the outer lamina may be lifted from the inner lamina where the inner laminae are sealed together and the carton may be opened by tearing the inner lamina along the said hinge lines.

2. A carton made of laminated material comprising an inner lamina of a readily tearable non-porous material and an outer lamina of paperboard, said laminae being bonded together, said carton having a plurality of panels connected together to form a tubular structure, said panels having hinge lines at corresponding edges at one end of said structure, said edges being aligned in juxtaposition to define a plurality of end flaps adapted to be successively folded inwardly to superposed relation to close the carton, the end flap which is first folded inwardly having a central portion substantially coextensive with the space defined by said hinge lines and having outwardly projecting tabs, the inner lamina of said tabs being sealed to the inner lamina of others of said end flaps to seal said carton, the inner lamina of the carton material being delaminated from the outer lamina in said outwardly projecting tabs completely in the area where the inner laminae are sealed together whereby the outer lamina of said tabs may be lifted from the inner lamina in that portion where the inner laminae are sealed together and the carton may be opened by tearing the inner lamina along the said hinge lines.

3. A carton made of laminated material having inner and outer laminae bonded together, said carton having a plurality of panels connected together to form a tubular structure, one end of said tubular structure being defined by a plurality of hinge lines at corresponding edges of said panels, said hinge lines extending transversely across said panels and aligned in juxtaposition, a plurality of end flaps connected to respective panels by said hinge lines and successively folded inwardly in superposed relation to seal the end of the carton, the innermost end flap which is folded to an underlying position having a. central portion which is substantially coextensive with the area bounded by said hinge lines and having outwardly projecting tabs, the inner lamina of said tabs being sealed to the inner lamina of the others of said end flaps and the outer lamina of said tabs being delaminated from the inner lamina completely over the area of said tabs.

4. A carton made of laminated material having inner and outer laminae bonded together, said carton having a plurality of panels connected together to form a tubular structure, one end of said tubular structure being defined by a plurality of hinge lines at corresponding edges of said panels, said hinge lines extending transversely across said panels and aligned in juxtaposition, a plurality of end fiaps connected to respective panels by said hinge lines and successively folded inwardly in superposed relation to seal the end of the carton, the innermost end flap which is folded to an underlying position having a central portion which is substantially coextensive with the area bounded by said hinge lines and having outwardly projecting tabs, the inner lamina of said tabs being sealed to the inner lamina of the others of said end flaps and the outer lamina of said tabs being delaminated from the inner lamina completely over the area of said tabs, the outermost end fiap which is folded to an overlying position having a tear line of weakened structure extending a transversely completely across said flap adjacent its end nearest to its connecting hinge line, said outermost end flap having an area bonded to the surface of the end flap which is directly therebeneath near the edge of said outermost end flap opposite that edge defined by said 5 hinge line.

References Cited in the file of this patent UNITED STATES PATENTS 1,517,964 Drysdale Dec. 2, 1924 10 6 Guyer Mar. 21, 1939 Fisher et a1 Eune 20, 1939 Moore Apr. 9, 1940 Zinn Sept. 15, 1953 Zinn Dec. 1, 1953 Guyer Oct. 14, 1958 BenZon-Petersen May 12, 1959 

